The family cocker has always been very picky over food- one week she'll inhale chicken mince and the next won't touch it, and so on and so forth with different types of wet food.
She nearly always hates dry food, and the only thing she will religiously eat is chicken necks.
My parents (who I'm staying with for a while) have started a bad habit of feeding her table scraps, and treats, and so now not only will she refuse to eat anything except chicken necks or human food, she's begging every time I take out food for myself which I just hate in dogs.
They even hand feed her from a spoon sometimes to get her to eat 
My question is- how do I stop this? It's ridiculous. I've told them to stop giving her table scraps completely and only treats for training, and I read that you should put their food down, leave it for 20minutes then take it away and offer it again later and carry on until they eat.
They say a healthy dog won't starve but how long is too long to go without food? She hasn't eaten anything for about 36 hours at this point. She's drinking fine, and is one year old.